Interview.
Xavier Arbós Marín is a professor of constitutional law at the University of Barcelona. “The constitution says that a referendum can only summon the state. If you ask a question about independence, you leave the constitutional framework.”

We asked a Spanish constitutional scholar about Catalan independence

Xavier Arbós Marín is also a professor of constitutional law at the University of Barcelona. He was part of the PSOE Constitutional Reform Commission in 2015. Formerly independent, Arbós Marín now considers himself more federalist.

What will happen next week?

I cannot predict. But Tuesday’s parliamentary session does not challenge the Constitutional Tribunal. This does not prevent the CUP [the Popular Unity Candidacy, the Catalan party pushing for independence] from making a proposal to alter the agenda. But another group would have to make it, and at this time we don’t know if Junts pel Sí [the regional governing coalition] would support it. I don’t think we will have a DUI [the Spanish acronym for unilateral declaration of independence], at least not Tuesday.

What are the most constitutionally serious things that have happened so far?

For one thing, Sunday’s totally disproportionate intervention affected the physical integrity of many people. But another is that laws on the referendum and legal transitionality were approved: They explicitly rule in favor of the breaking of the constitutional order.

Do you have any remarks on the Constitutional Tribunal’s (TC) work?

It would have been possible to keep away from a problem that we all know to be of an especially political nature, and that the law alone will not resolve. Until 2013, the TC did not interfere in the resolutions of the autonomous parliaments; it stood at the door, so to speak, and gave the legal interpretation of the norms only once approved. But in 2014, it did something it’s never done: It cancelled a resolution of the Parliament without legal effects. This is beyond its powers. In addition, the People’s Party government that year, with an absolute majority, modified the law and put it at the forefront of the political conflict because it gave the court sanctions power. The Spanish government gave up doing politics and outsourced its responsibility to the TC.

This is why the separatists say they had no choice.

Everyone can use this argument. Even the Spanish government says it has no choice but to bring everything to the TC. The Generalitat has no authority to convene a referendum of any kind: If it does, it’s violating both the constitution and its own statute. People, parties, associations can do anything; that is not forbidden. Institutions can only do what they are authorized to do.

But the Catalan Statute makes it possible to convene consulates.

Only non-referendary ones — that is, those who do not use usual electoral instruments. The constitution says that a referendum can only summon the state. If you ask a question about independence, you leave the constitutional framework.

Is there a way to conduct this referendum without breaking the constitution?

Yes. That was proposed in April 2014 by the Catalan Parliament, which sent a delegation to the Congress to ask it to transfer powers to Catalonia to convene a referendum, a constitutionally conceivable mechanism. Some constitutionalists like me believe it is possible to have a non-binding referendum on independence — which isn’t to imply that this is advisable.

Does the right to self-determination prevail over constitutions?

It is true that international treaties such as the U.N. human rights treaty are part of the legal order. But the right to self-determination applies only in colonial cases, according to the interpretations that the U.N. has done over the years, giving priority to the principle of territorial integrity. Although the law on referendum invokes this right, I believe it cannot justify a secession.

And what about the “right to decide”?

Before campaigning under the right of self-determination, separatists used “the right to decide,” which was less dangerous. The thesis was that this right could be exercised either with a parliamentary statement or with a plebiscite or plebiscite election, such as those of 2015. In fact, the parliament out of those elections had decided to start the process of secession, and did not foresee any other referendum than that at the end of the process to ratify the new Catalan constitution. Which made sense. A year ago Puigdemont changed the idea, and the referendum option appeared but needed a new justification.

In the current constitutional system, what jurisdiction does an autonomous community like Catalonia have?

It has legislative capacity in many respects, especially in the key areas of health, education and social welfare. But there is an important difference with Italy. The Congress cannot modify an autonomous law but must pass through a conflict of jurisdiction with the TC. Compared with Italy, the guarantee of self-government is greater. Another difference is that skills can change from community to community. This is because historically Spain has always had problems defining its territorial organization because there were realities such as Catalonia, Basque country and Galicia, which had self-government and others did not. The constitution left the door open to those who wanted to adjoin, but the process took place too quickly.